The hot metal full pretreatment and less-slag steelmaking process constituted a platform to produce clean steel with low cost and rapid pace and also realized a professional production line. The w[P] can be less than ...The hot metal full pretreatment and less-slag steelmaking process constituted a platform to produce clean steel with low cost and rapid pace and also realized a professional production line. The w[P] can be less than 0.030% at the end of De-P converter and 0.006% at the end of De-C converter. The w[N] in steel can be less than 15×10-6 at the stirring station. This production line can make clean steel steadily used for auto sheet or pipeline, for example X65 MS. The De-C slag was left in the converter for the next heat and recycled to De-P converter to reduce lime consumption, which has a great benefit for the cost saving.展开更多
Focused on the hot metal pretreatment process in the torpedo-car and based on the powder injection metallurgy principle, a kinetic model for dephosphorization of high-phosphorus hot metal pretreatment was developed. T...Focused on the hot metal pretreatment process in the torpedo-car and based on the powder injection metallurgy principle, a kinetic model for dephosphorization of high-phosphorus hot metal pretreatment was developed. The validity of this model was verified by comparison between the experimental results in laboratory and the calculated results. The influences of dephosphorization capacity of molten slag and technological conditions on the dephosphorization efficiency were calculated by applying the model. The results show that lower temperatures are favorable to dephosphorization, CaO content in slag should be controlled at about 50%, suitable initial phosphorus content in the hot metal with higher phosphorus contents is about 0.35% by comprehensively considering various factors, slag systems of higher iron oxide content and higher basicity have higher capacity of dephosphorization.展开更多
The purpose of the study is to decrease content of CaF2 in dephosphorization slag. The dephosphorization effects of CaF2 replaced by B2O3 were investigated. The dephosphorization experiments were carried out at 1 450 ...The purpose of the study is to decrease content of CaF2 in dephosphorization slag. The dephosphorization effects of CaF2 replaced by B2O3 were investigated. The dephosphorization experiments were carried out at 1 450 ℃ in air atmosphere. The results show that the melting points and dephosphorization ratios change little when CaF2 was replaced by B2O3. The dephosphorization ratios are all greater than 80% and melting points can meet the requirement of hot metal pretreatment. Because of the change of alkalinity caused by B2 03, the oxidation of slag increases with increasing of B2 Oa contents. It is beneficial to pre-dephosphorization. As a result, for decreasing its pollution, CaF2 can be replaced by B2Oa to dispose fluoride-free pre-dephosphorization slag.展开更多
The paper describes the recent developing situation and the latest research achievements of refractory for hot metal pretreatment. The relationship among desiliconization, dephosphorization and desulphurization techni...The paper describes the recent developing situation and the latest research achievements of refractory for hot metal pretreatment. The relationship among desiliconization, dephosphorization and desulphurization techniques and the main corrosion reactions by various treating agents is analyzed. Some improving measures for several problems in practice are put forward while we anticipate the future developing direction of refractory for hot metal pretreatment.展开更多
The chromium recycling from the stainless steel dust of an argon-oxygen decarburization (AOD) furnace during a hot metal pretreatment process was investigated. Experiments at different temperatures or with different...The chromium recycling from the stainless steel dust of an argon-oxygen decarburization (AOD) furnace during a hot metal pretreatment process was investigated. Experiments at different temperatures or with different amounts of AOD dusts were carried out in a laboratory furnace equipped with MoSi2 heating elements and subsequently industrial experiments were conducted in a stainless steelmaking factory, in order to study the thermodynamic mechanism of C and Si reacted with Cr2O3 to get Cr from AOD dust. The results showed that the reaction between C and Cr2 O1 occurred below 1572.18 K. Although its reducing ability was weaker than that of Si, C enabled the Cr in Cr2O3 in the AOD dust to be recycled using the Si in the slag. By combining the AOD dust added in an earlier stage, the hot metal pretreatment slag added in a later stage could not only recycle Cr from AOD dust but also remove Si, S, and P. Higher hot metal temperatures resulted in higher Cr content and lower remained P concentration in the molten iron.展开更多
文摘The hot metal full pretreatment and less-slag steelmaking process constituted a platform to produce clean steel with low cost and rapid pace and also realized a professional production line. The w[P] can be less than 0.030% at the end of De-P converter and 0.006% at the end of De-C converter. The w[N] in steel can be less than 15×10-6 at the stirring station. This production line can make clean steel steadily used for auto sheet or pipeline, for example X65 MS. The De-C slag was left in the converter for the next heat and recycled to De-P converter to reduce lime consumption, which has a great benefit for the cost saving.
文摘Focused on the hot metal pretreatment process in the torpedo-car and based on the powder injection metallurgy principle, a kinetic model for dephosphorization of high-phosphorus hot metal pretreatment was developed. The validity of this model was verified by comparison between the experimental results in laboratory and the calculated results. The influences of dephosphorization capacity of molten slag and technological conditions on the dephosphorization efficiency were calculated by applying the model. The results show that lower temperatures are favorable to dephosphorization, CaO content in slag should be controlled at about 50%, suitable initial phosphorus content in the hot metal with higher phosphorus contents is about 0.35% by comprehensively considering various factors, slag systems of higher iron oxide content and higher basicity have higher capacity of dephosphorization.
基金Item Sponsored by National Natural Science Foundation of China and Baosteel(50674001)
文摘The purpose of the study is to decrease content of CaF2 in dephosphorization slag. The dephosphorization effects of CaF2 replaced by B2O3 were investigated. The dephosphorization experiments were carried out at 1 450 ℃ in air atmosphere. The results show that the melting points and dephosphorization ratios change little when CaF2 was replaced by B2O3. The dephosphorization ratios are all greater than 80% and melting points can meet the requirement of hot metal pretreatment. Because of the change of alkalinity caused by B2 03, the oxidation of slag increases with increasing of B2 Oa contents. It is beneficial to pre-dephosphorization. As a result, for decreasing its pollution, CaF2 can be replaced by B2Oa to dispose fluoride-free pre-dephosphorization slag.
文摘The paper describes the recent developing situation and the latest research achievements of refractory for hot metal pretreatment. The relationship among desiliconization, dephosphorization and desulphurization techniques and the main corrosion reactions by various treating agents is analyzed. Some improving measures for several problems in practice are put forward while we anticipate the future developing direction of refractory for hot metal pretreatment.
基金Sponsored by National Natural Science Foundation of China(51574063)National Science and Technology Support Program of China(2015BAF03B00)+1 种基金Doctor Research Startup Foundation of Liaoning Institute of Science and Technology of China(1406B06)Program for Liaoning Excellent Talents in University of China(LJQ2015056)
文摘The chromium recycling from the stainless steel dust of an argon-oxygen decarburization (AOD) furnace during a hot metal pretreatment process was investigated. Experiments at different temperatures or with different amounts of AOD dusts were carried out in a laboratory furnace equipped with MoSi2 heating elements and subsequently industrial experiments were conducted in a stainless steelmaking factory, in order to study the thermodynamic mechanism of C and Si reacted with Cr2O3 to get Cr from AOD dust. The results showed that the reaction between C and Cr2 O1 occurred below 1572.18 K. Although its reducing ability was weaker than that of Si, C enabled the Cr in Cr2O3 in the AOD dust to be recycled using the Si in the slag. By combining the AOD dust added in an earlier stage, the hot metal pretreatment slag added in a later stage could not only recycle Cr from AOD dust but also remove Si, S, and P. Higher hot metal temperatures resulted in higher Cr content and lower remained P concentration in the molten iron.